JPH05106547A - Negative pressure air power generation device - Google Patents

Abstract

PURPOSE:To recover unused energy at a high efficiency by generating negative pressure air from water currents, and rotating an air turbine with it for converting energy of brine discharged at a low level in a thermal power generation plant, nuclear power generation plant, etc., so as to drive a power generator. CONSTITUTION:A negative pressure air power generation device comprises a water current air suction means 1 provided in brine discharge passage, and a power generator 7 driven by an air turbine 6 rotated at a high speed by negative pressure air generated by it. The water current air suction means 1 comprises a venturi tube 2, an air injection port 3 provided at its diameter contracted part, and a suction tube 4 connected to it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a negative pressure air power generation device for generating negative pressure air from a water flow having a low water level and a low flow velocity to drive an air turbine to generate electricity.

[0002]

2. Description of the Related Art Thermal power plants, nuclear power plants, or L
At NG bases and the like, a large amount of seawater is used for cooling the condenser and vaporizing LNG, and after use, it is returned to the sea as it is.
Seawater is returned to the sea from power plants, etc., so 1m from the sea level
Although there is a water level difference between the front and back, the water level difference is so small that no attempt has been made to generate electricity using this, and it is left as unused energy. Therefore, if this unused energy is used for power generation, a considerably large economic effect can be expected at a large-scale power plant or the like.

As a method of generating electric power by utilizing natural energy having a small water level difference, for example, a power generation method such as wave power generation or tidal power generation is known. In such a power generation system, a propeller turbine, a Kaplan turbine, a tubular turbine or the like has been generally used conventionally. In the above-mentioned conventional power generation method using a water turbine, when the water level difference is a low water level difference of about 1 m, the energy recovery efficiency of both methods is extremely poor, and one of the attempts to improve this is disclosed in Japanese Patent Laid-Open No. Hei 2 -223681
A power generation method based on the publication is proposed.

The power generation method according to this publication is provided with a primary converter for wave energy that forms a predetermined water level difference on the sea surface of a sea using a breakwater or the like, and a downward conduit, a gas / water separation tank, and an upward conduit are provided in this device. Is a method of mixing the air into the water flow generated in the conduit by utilizing the water level difference, and driving the air turbine using the compressed air generated at the deepest water pressure in the conduit to generate electricity. ..

[0005]

When planning a power generation system for recovering unused energy of seawater used in thermal power plants, nuclear power plants, etc., the following conditions must be taken into consideration. (1) The difference in water level is as low as around 1 m, and it can be used effectively. (2) Do not affect the operation of the original equipment such as thermal power and nuclear power plants. Therefore, it is not necessary to stop the flow of seawater to be used at the time of planned equipment installation or repair such as failure. (3) Equipment costs must be on an economic basis.

When considering a power generator suitable for such a condition, the conventional propeller turbine, Kaplan turbine, tubular turbine or the like is not suitable because the water level difference is too low. As is done. In addition to the above-mentioned conventional water turbine method, there are, for example, a cross flow turbine and an open-circulation turbine. However, in both cases, the water level difference is too low and energy recovery efficiency is poor. Further, a water level adjusting device upstream of the drainage channel and a lifting mechanism for the water turbine device are required, which is not economical.

Since the power generation system according to the above publication is designed so that it can be installed at a place where the water level difference is about 1 m, it is possible to generate electricity by using seawater energy with a low water level difference in thermal power plants, nuclear power plants, etc. Can fit into. However, a water-flow air compression device must be installed in the drainage channel, which requires stopping the flow of seawater when the device is installed, which again cannot be adopted.

The present invention, when planning a power generation facility for recovering unused energy of low-level seawater used in the above-mentioned thermal power plants, nuclear power plants, etc., causes various problems when the conventional power generation system is adopted. In consideration of the above, it is an object to provide an economical power generation device that is suitable for recovering seawater energy with a low water level difference and does not significantly affect existing power plant facilities.

[0009]

In order to solve the above-mentioned problems, the present invention provides a drainage channel for seawater discharged with a low water level difference.
A water flow air suction consisting of a horizontal inlet pipe bent downward and connected with a Venturi pipe having a reduced diameter portion and an expanded portion, an air inlet being provided at the reduced diameter portion, and a suction pipe connected to the air inlet. A device is provided, the other end of the suction pipe is connected to an exhaust port of an air turbine, and the air turbine is rotated by negative pressure air generated by the suction device, and a generator connected to the air turbine and rotationally driven. This is the structure of the negative pressure air generator.

In the above-mentioned hydroelectric power generator, another curved pipe portion is provided between the inlet pipe and the curved pipe portion, and the inlet pipe is provided downward and so as to be immersed under the upstream water surface to form a siphon as a whole. However, the venturi tube may be a siphon type venturi tube.

Alternatively, a siphon type Venturi tube as the water flow air suction device is provided with the Venturi tube, and the suction pipes connected to the respective air inlets are joined on the way to be connected to the outlet of the air turbine. It is also possible to connect a midway of the venturi pipe until the suction pipe merges with the upper end of the siphon type Venturi pipe by a communication pipe, and insert a throttle valve in the communication pipe.

Further, in any one of the negative pressure air generators, two upper and lower lubricating oil tanks are installed for the air turbine, and a communication pipe connected to the discharge side of the air turbine is connected to the lubricating oil of the upper tank. Connected to the space of the tank and the exhaust oil pipe from the bearing of the air turbine to this tank space, further connecting the lubricating oil tank of the lower tank and the bearing with the oil supply pipe, using negative pressure air in the suction pipe The bearing may be provided with a lubricating oil supply device that automatically lubricates the bearing.

[0013]

Since the present invention is configured as described above, when a water flow hits the water flow air suction device provided in the drainage channel, the flow velocity of the water flow passing through the diameter reduced portion in the venturi pipe increases and the hydrostatic pressure increases. As a result, the atmosphere is sucked from the air inlet through the suction pipe, and a negative pressure air flow is generated in the suction pipe. The flow of the negative pressure air is guided to the exhaust port of the air turbine by the suction pipe and rotates the rotor of the air turbine. The inlet of the air turbine is open to the atmosphere.
When the air turbine rotates, a generator connected to the air turbine is driven to generate electricity.

In the second solution, the venturi tube is replaced with a siphon type venturi tube. Therefore, by setting the air suction portion higher than the upstream water surface, a large negative pressure can be easily formed, and as a result, the flow velocity at the diameter reducing portion of the Venturi tube can be reduced. Therefore, the recovery efficiency is higher than that of the first invention.

In a third solution means, a water flow air suction device provided with the venturi pipe and a siphon type venturi pipe is used. Therefore, in the second solution, the problem that the siphon is not formed at the time of start-up and the automatic start-up does not occur, the automatic start-up becomes possible, the flow of negative pressure air further increases, and the energy recovery efficiency is increased. Is improved.

At the time of startup, the air in the siphon type Venturi tube is sucked by the water flow air suction device of the venturi pipe type, and when the pipe is filled with seawater, both suction devices are operated to generate a negative pressure air flow.

In the lubricating oil supply device attached to any one of the above negative pressure air generators, negative pressure air sucks the discharge side of the bearing by a communication pipe connected to the discharge side of the air turbine, and the suction pressure causes the inside of the bearing to be sucked. When the lubricating oil is discharged, the lubricating oil is sent from the lubricating oil tank in the lower tank to automatically supply the lubricating oil.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an overall schematic view of a negative pressure air power generation device according to the present invention installed in a drainage channel for returning seawater used in thermal power plants, nuclear power plants, etc. to the sea. As shown in the drawing, a drainage channel is provided through the open conduit K to the underdrain U with respect to the quay W in contact with the sea surface S, and the water level difference H between the upstream water surface of the drainage channel and the sea surface S is about 1 m. .. The water flow air suction device 1 is provided at a position in the drainage path where the open conduit K is moved to the underdrain U. This water flow air suction device 1 comprises a Venturi tube 2 and a suction tube 4 connected to an air injection port 3 provided in a diameter reduced portion thereof.

The Venturi tube 2, as shown in FIG.
An elbow 12 is attached to an inlet pipe 11 horizontally provided on the upstream water surface F.
A bubble mixing section 14 in which an air injection port 3 for sucking air is provided in a downwardly-reduced tube of which a downwardly extending outlet is connected, an expanded tube section 15 having a gradually expanded diameter thereafter, and a drain tube 16 are connected. Become. The suction pipe 4 is connected to the air inlet 3 via a connection pipe 13 attached to the outer periphery of the bubble mixing section 14. Of course, it may be directly connected to the air inlet 3 without providing the connecting pipe 13. The other end of the suction pipe 4 is guided to the outlet of the air turbine 6 of the power generator 5, and the inlet of the air turbine 6 is open to the atmosphere. The air turbine 6 has a generator 7
Are directly connected to drive the air turbine 6 to generate electricity.

FIG. 5 shows a schematic structure of the power generator 5. The air turbine 6 sucks air from the atmosphere to rotate a turbine rotor, and the sucked air is discharged from the radial direction to the axial direction and flows into the suction pipe 4. Therefore, the air turbine 6 is rotationally driven by the negative pressure of the suction pipe 4. Guide vanes and guide vanes may be provided on the outer periphery of the turbine rotor (not shown). The air turbine 6 is supported by a bearing 8 by a bearing 8 and is connected to a generator 7 by a shaft joint 9 using a coil spring. This air turbine 6 uses a single-stage radial flow turbine because of its small capacity. Also, the generator 7
A DC motor may be used for the power generation, and the back electromotive force may be used to generate electricity.
An AC synchronous generator or an induction generator may be adopted because it rotates at a high speed of pm.

FIG. 6 shows a lubricating system for the bearing 8 of the power generator 5. This lubricating oil supply device is not provided with an oil supply pump, and is composed of upper and lower two tanks of oil tanks 21 and 22 shown in the figure, and the negative oil pressure of the turbine is used during turbine operation to provide an upper oil tank via the communication pipe 4b. Negative pressure in the space inside 21,
A negative pressure is also applied to the inside of the bearing 8 communicated with the oil drain pipe 24 to suck up the oil from the lower oil tank 22 through the oil supply pipe 23.
It is configured to refuel the turbine shaft. While the turbine is stopped, the return valve 26 of the return line 25 is opened to return the oil discharged from the oil tank 21 to the oil tank 22. With such an oil supply device, a lubricating action can be obtained for a long period of time, and oil replenishment becomes unnecessary. A throttle valve 27 is opened and closed as necessary.

Electric power is generated by the power generator of this embodiment having the above-mentioned structure as follows. A water flow generated by the water level difference H of the seawater flows around the water flow air suction device 1 installed in the drainage channel, and this water flow also flows into the Venturi pipe 2. In the Venturi tube 2, the diameter of the water flow is reduced at the reduction tube 14, so that the flow velocity is increased, so that the dynamic pressure is increased and the static pressure is reduced. When this static pressure is reduced, air is continuously sucked from the air inlet 3 provided in the bubble mixing portion 14, and a negative pressure is generated in the suction pipe 4. Since the other end of the suction pipe 4 communicates with the air turbine 6, the negative pressure air drives the air turbine 6 to rotate. Then, power is generated by a generator 7 connected to the air turbine 6.

FIG. 3 shows a water flow air suction device 1'of the second embodiment.
Indicates. In this embodiment, another elbow 12'a is inserted between the elbow 12 and the inlet pipe 11 of the apparatus shown in FIG. 2, and the inlet pipe 11 'is directed downward and immersed in the upstream water surface to form a siphon pipe as a whole. is doing. The siphon type Venturi tube 2'is provided at a position where the upper end is appropriately higher than the upstream water surface. Others are the same as the embodiment of the figure,
The same reference numerals have the same dashes attached to the same components.

The operation of this embodiment is basically the same as that of the first embodiment, but since the whole is a siphon tube,
The suction pressure by the siphon type Venturi tube 2'is larger than that of the first embodiment, and therefore the efficiency is higher.
In addition, in this embodiment, since the upper end of the siphon type Venturi tube 2'is projected about 1 m above the water surface, a siphon is not formed at the time of startup and seawater does not flow. Therefore, in this case, some activation assisting means is required. As one of the methods, a method may be used in which a suction pump is connected in the middle of the suction tube 4 and the air in the siphon-type Venturi tube 2'is sucked only when the suction pump is activated (not shown).

FIG. 4 shows a schematic diagram of the third embodiment. This embodiment is a combination of the first embodiment and the second embodiment. As described above, in the siphon type Venturi tube system of the second embodiment, it is necessary to fill the inside of the tube with seawater by the starting assisting means at the time of starting. Therefore, in this embodiment, the water-flow air suction device 1 of the first embodiment and the second embodiment,
1'is installed side-by-side so that it can be automatically started, and it is intended to further improve efficiency. For this reason, both suction devices 1, 1 ′ are installed, and as shown in the drawing, the suction pipe 4,
4'is connected to each other in the middle of the route leading to the air turbine 6 to form one suction pipe 4X, and the middle of the suction pipe 4 and the upper end of the siphon type Venturi pipe 2'of the suction device 1'are connected by the communication pipe 4a. This is provided with a throttle valve 10 '.

When the suction device 1'is activated, first, the throttle valve 10 'is opened in the middle of the suction pipe 4X leading to the air turbine 6 and the negative pressure of the suction device 1 causes the air in the upper end of the siphon type Venturi pipe 2'. Is sucked into negative pressure and filled with seawater. When the siphon tube 2'is filled with seawater, the suction device 1'is activated. When the suction device 1'starts up, the throttle valve 10 on the way to the air turbine 6 is opened, and when the throttle valve 10 'is closed, both suction devices 1 and 1'start normal operation.

[0027]

As described above in detail, in the power generator of the present invention, the suction pipe is connected to the air injection port provided in each bubble mixing portion of the venturi pipe, the siphon pipe with the venturi pipe, or the combination pipe of the both. Since the air turbine that is driven to rotate by the negative pressure generated thereby and the generator that generates electricity by this turbine are provided, the structure is extremely simple, and compressed air is used to drive the air turbine by the negative pressure. Unlike the system for generating electricity, a water-water separation tank and a long communication pipe are not required, and therefore installation work, failure repairs, maintenance and inspection work of the power generator are easy, and it is not necessary to stop the flow of seawater in the drainage channel during that time. Further, even if the water level difference is low, the water flow energy is converted into a negative pressure air flow with high efficiency to generate electric power, so that various advantages such as high energy recovery efficiency and economic efficiency can be obtained. ..

[Brief description of drawings]

FIG. 1 is a schematic view of an entire apparatus in which a negative pressure air power generator according to a first embodiment is installed in a drainage channel.

FIG. 2 is a schematic view of a water flow air suction device according to the first embodiment.

FIG. 3 is a schematic view of a water flow air suction device according to a second embodiment.

FIG. 4 is a schematic view of a water flow air suction device according to a third embodiment.

FIG. 5 is a schematic external view of a power generator.

FIG. 6 is a schematic system diagram of an oil supply device for lubricating a bearing.

[Explanation of symbols]

 1, 1'Water flow air suction device 2 Venturi pipe 2'Siphon type Venturi pipe 3, 3'Air inlet 4, 4 ', 4X suction pipe 5 Power generation unit 6 Air turbine 7 Generator 11, 11' Inlet pipe 14, 14 'Bubble mixing section 15, 15' Expansion section

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Tsuneki Kamiki 3-3-22 Nakanoshima, Kita-ku, Osaka City Kansai Electric Power Co., Inc. (72) Yoshiaki Tamura 3-3-22 Nakanoshima, Kita-ku, Osaka Kansai Denryoku Co., Ltd. (72) Inventor Katsuyoshi Ogawa 3-3-22 Nakanoshima, Kita-ku, Osaka Kansai Denryoku Co., Ltd. (72) Inventor Masahisa Fujimoto 2-1-1 Niihama, Arai-cho, Takasago Mitsubishi Heavy Industries Takasago Manufacturing Co., Ltd. (72) Inventor Masayuki Kita 1-1-1, Niihama, Arai-cho, Takasago City Mitsubishi Heavy Industries Takasago Manufacturing Co., Ltd.

Claims (4)

[Claims] 1. In a drainage channel of seawater discharged with a low water level difference, a pipe following a horizontal inlet pipe is bent downward, and a Venturi pipe having a diameter reducing portion and an expanding portion is connected to the diameter reducing portion. A water flow air suction device is provided in which an air inlet is provided and a suction pipe is connected to the air inlet, the other end of the suction pipe is connected to the outlet of the air turbine, and the negative pressure air generated by the suction device rotates. A negative pressure air power generation device comprising an air turbine and a power generator connected to the air turbine and rotationally driven. 2. Another curved pipe portion is provided between the inlet pipe and the curved pipe portion, and the inlet pipe is provided so as to face downward and below the upstream water surface to form a siphon as a whole. The negative pressure air power generation device according to claim 1, wherein the venturi tube is a siphon type venturi tube. 3. A siphon type Venturi pipe as the water flow air suction device is provided with the Venturi pipe, and the suction pipes connected to the respective air inlets are joined on the way to be connected to the outlet of the air turbine. The negative pressure pneumatic power generation according to claim 2, wherein the middle of the path of the suction pipe of the Venturi pipe and the upper end of the siphon type Venturi pipe are connected by a communication pipe, and a throttle valve is inserted in the communication pipe. apparatus. 4. The upper and lower two tanks of lubricating oil tanks are installed with respect to the air turbine, the communication pipe connected to the discharge side of the air turbine is connected to the space of the lubricating oil tank of the upper tank, and the bearing of the air turbine. A lubricating oil supply device in which an oil discharge pipe from the above is connected to this tank space, the lubricating oil tank of the lower tank is further connected to the bearing by an oil supply pipe, and the negative pressure air in the suction pipe is used to automatically lubricate the bearing. The negative pressure air power generation device according to any one of claims 1 to 3, further comprising: